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How to best power a camera on DC with fluctuating inputs.

I

IHaveThePower

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Jun 4, 2022
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Hi
So I have a security system which I've been running at my off grid lot and I've run into a problem..
I am powering the cameras directly on dc where I've cut the ac adapter and installed fuses to protect the cameras.
The cameras don't like voltages over 12ish v and when I have them connected directly at the 12v battery they fail to run when the sun is out because the panels are producing between 17-21v
If I install a 24v step down it will run when the sun it out but when the sun sets the voltage into the converter will drop and it will stop giving 12v. [I'm assuming]
Besides going back to running them on ac is there a solution.
The converter I have on my 24v system runs at 17-40v, it works fine because the battery is 24v but on my smaller 12v setup the same converter would probably not work the same. I assume the voltage dropping to less than 17v when the sun sets will cut power on the output side.

The reason I run them on dc besides the power savings is they are away from the Inverter and its just easier to tie them directly into the battery.
 
IHaveThePower said:
Hi
So I have a security system which I've been running at my off grid lot and I've run into a problem..
I am powering the cameras directly on dc where I've cut the ac adapter and installed fuses to protect the cameras.
The cameras don't like voltages over 12ish v and when I have them connected directly at the 12v battery they fail to run when the sun is out because the panels are producing between 17-21v
If I install a 24v step down it will run when the sun it out but when the sun sets the voltage into the converter will drop and it will stop giving 12v. [I'm assuming]
Besides going back to running them on ac is there a solution.
The converter I have on my 24v system runs at 17-40v, it works fine because the battery is 24v but on my smaller 12v setup the same converter would probably not work the same. I assume the voltage dropping to less than 17v when the sun sets will cut power on the output side.

The reason I run them on dc besides the power savings is they are away from the Inverter and its just easier to tie them directly into the battery.
Click to expand...
Are you saying that if you check the Voltage at the battery terminals you are seeing 17~21V when the sun is out when it is being charged by the charge controller?
What kind of charge controller are you using?
 
Bud Martin said:
Are you saying that if you check the Voltage at the battery terminals you are seeing 17~21V when the sun is out when it is being charged by the charge controller?
What kind of charge controller are you using?
Click to expand...
You know you're right that's way too high for charging voltage isn't it. I'll have to check that again.
Maybe the CC has malfunctioned
 
What kind of batteries are you using?
May the SCC is performing battery equalization.
BTW, you have two threads with basically the same question, it is a little to hard to follow.
batteryuniversity.com

BU-404: What is Equalizing Charge?

BU meta description needed...
batteryuniversity.com batteryuniversity.com
 
Bud Martin said:
What kind of batteries are you using?
May the SCC is performing battery equalization.
BTW, you have two threads with basically the same question, it is a little to hard to follow.
batteryuniversity.com

BU-404: What is Equalizing Charge?

BU meta description needed...
batteryuniversity.com batteryuniversity.com
Click to expand...
That's strange. I'm not sure why two threads were created.
The battery is a rebranded 12v offshore called polar battery. Bought it from polar battery while traveling across Canada.
I called them last week because the bms meter on bluetooth started failing to show charge % and they said they had recalled the battery so I'm sending it back. On their buck.
Today the scc shows 13v so maybe it was equalizing but it's a pretty basic pwm so I'm not sure that's possible.
I'll check it throughout the day.
Seems to be working fine but I ordered an mppt renogy 30a last night.
I'll swap that out anyways when I get it
 
Check the SCC user manual or scroll through the display setting to see if there is setting for equalization, most of them have this function, you can turn it off since it is for Lead acid battery only so it should not be used on your batteries, or you can set the equalizing Voltage to really low, make sure you disable that on the Renogy too.
 
Bud Martin said:
Check the SCC user manual or scroll through the display setting to see if there is setting for equalization, most of them have this function, you can turn it off since it is for Lead acid battery only so it should not be used on your batteries, or you can set the equalizing Voltage to really low, make sure you disable that on the Renogy too.
Click to expand...
I will thank you.
It lists an equalize voltage of 14.8
The new renogy one is supposed to be tailored for lithium so will see what settings it has.
I am wondering if because this pwm cc is a 12/24 that the voltage from the panels at high output time of day is fooling the CC to thinking it's hooked up to a 24v battery. So it's output jumps to 24v limits yet the panels don't push 24v power. Then the bms is perhaps limiting input voltage or cutting off charging at its set limit allowing the battery to charge.
 
IHaveThePower said:
I will thank you.
It lists an equalize voltage of 14.8
The new renogy one is supposed to be tailored for lithium so will see what settings it has.
I am wondering if because this pwm cc is a 12/24 that the voltage from the panels at high output time of day is fooling the CC to thinking it's hooked up to a 24v battery. So it's output jumps to 24v limits yet the panels don't push 24v power. Then the bms is perhaps limiting input voltage or cutting off charging at its set limit allowing the battery to charge.
Click to expand...
Good SCC should be able to detect the battery Voltage so it'll set itself up correctly, it is very important that you must connect the battery to the SCC first so it will see the properly battery Voltage to set itself to the correct running Voltage, do not connect the panels first.
 
Bud Martin said:
Good SCC should be able to detect the battery Voltage so it'll set itself up correctly, it is very important that you must connect the battery to the SCC first so it will see the properly battery Voltage to set itself to the correct running Voltage, do not connect the panels first.
Click to expand...
Hmm OK I'll have to keep that in mind. Perhaps I've accidentally tricked the scc by touching panel wires to the scc while hooking it up last time I had it apart to test the battery.
Thanks
 
If you look at the user manual of your SCC, there will be warning about not to have panels connected to the SCC without connecting the battery first and not disconnecting the battery when the panel is still connected unless you do that during night time.
 
IHaveThePower said:
Hi
So I have a security system which I've been running at my off grid lot and I've run into a problem..
I am powering the cameras directly on dc where I've cut the ac adapter and installed fuses to protect the cameras.
The cameras don't like voltages over 12ish v and when I have them connected directly at the 12v battery they fail to run when the sun is out because the panels are producing between 17-21v
If I install a 24v step down it will run when the sun it out but when the sun sets the voltage into the converter will drop and it will stop giving 12v. [I'm assuming]
Besides going back to running them on ac is there a solution.
The converter I have on my 24v system runs at 17-40v, it works fine because the battery is 24v but on my smaller 12v setup the same converter would probably not work the same. I assume the voltage dropping to less than 17v when the sun sets will cut power on the output side.

The reason I run them on dc besides the power savings is they are away from the Inverter and its just easier to tie them directly into the battery.
Click to expand...

I always recommend running a DC-DC stabilizer when using any sensitive electronics device (instead of raw fluctuating battery voltage)...

You need a converter that is boost and buck in the same box, so you can set it to 12v on the output, and the input voltage can go low or high from the set output voltage and still work. There are a bunch of cheap Amazon ones, but some of them mis-advertise and say they do boost and buck but really don't (have to read the reviews to find people who tested boost and buck).

I like these ones myself:

Manual on it:

It's an eval board, but works good for normal use (for me anyways)...


Input Voltage:9 V to 53 V
Output Voltage:9.6 V to 48 V

True boost and buck converter (supply up to 8a output, have a pot screw to adjust the output voltage)...

1660285932980.png
 
Last edited:
Samsonite801 said:
I always recommend running a DC-DC stabilizer when using any sensitive electronics device (instead of raw fluctuating battery voltage)...

You need a converter that is boost and buck in the same box, so you can set it to 12v on the output, and the input voltage can go low or high from the set output voltage and still work. There are a bunch of cheap Amazon ones, but some of them mis-advertise and say they do boost and buck but really don't (have to read the reviews to find people who tested boost and buck).

I like these ones myself:

Manual on it:

It's an eval board, but works good for normal use (for me anyways)...


Input Voltage:9 V to 53 V
Output Voltage:9.6 V to 48 V

True boost and buck converter (supply up to 8a output, have a pot screw to adjust the output voltage)...

View attachment 106515
Click to expand...
Awesome thanks.
Makes total sense, I was just relying on the fuse on that particular camera but on my other camera I run it off the 24v > 12v converter. I'll grab one of these and try it out.
 
Bud Martin said:
If you look at the user manual of your SCC, there will be warning about not to have panels connected to the SCC without connecting the battery first and not disconnecting the battery when the panel is still connected unless you do that during night time.
Click to expand...
Yes for sure, I've been following that on my larger setup. Battery to cc then panels on if I'm ever reconnecting and the reverse when disconnecting.
 
IHaveThePower said:
Awesome thanks.
Makes total sense, I was just relying on the fuse on that particular camera but on my other camera I run it off the 24v > 12v converter. I'll grab one of these and try it out.
Click to expand...

There's also this site which I've bought several different DC-DC converters (some of which do buck/boost, just have to check out the individual ones):

DC/DC Converters, to convert voltage up or down, retail, wholesale, off-the-shelf and custom, DC to DC converters 5 watts to 1500 watts, voltage from 1.5V to 72V, DC/DC power supplies

DC/DC converters for OEMs DC/DC power supplies including car to laptop, modules, bricks, and custom converters, DC/DC regulator
www.powerstream.com

The key here is you want to find something that meets the amps load requirement of your camera, has a 12v output, but the input volts can operate well within the range that your battery bank will every operate in normally...

Just another option in case you wanted to see more options, because you may not need one that supports 8a. It is a good one though, I have been using that TDK Lambda one most recently, for my Starlink power injector..
 
IHaveThePower said:
Hi
So I have a security system which I've been running at my off grid lot and I've run into a problem..
I am powering the cameras directly on dc where I've cut the ac adapter and installed fuses to protect the cameras.
The cameras don't like voltages over 12ish v and when I have them connected directly at the 12v battery they fail to run when the sun is out because the panels are producing between 17-21v
If I install a 24v step down it will run when the sun it out but when the sun sets the voltage into the converter will drop and it will stop giving 12v. [I'm assuming]
Besides going back to running them on ac is there a solution.
The converter I have on my 24v system runs at 17-40v, it works fine because the battery is 24v but on my smaller 12v setup the same converter would probably not work the same. I assume the voltage dropping to less than 17v when the sun sets will cut power on the output side.

The reason I run them on dc besides the power savings is they are away from the Inverter and its just easier to tie them directly into the battery.
Click to expand...
use these, they are buck boost so can handle below 12v and above 12v inputs, add a cooling fan if pushing many amps

www.aliexpress.com

3.95US $ 15% OFF|Dc-dc 5-30v To 1.25-30v 12v 24v 8a Automatic Adjustable Step Up Down Boost Buck Converter Power Module Voltage Regulator For Car - Voltage Regulators/stabilizers - AliExpress

Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com www.aliexpress.com
 
Goboatingnow said:
use these, they are buck boost so can handle below 12v and above 12v inputs, add a cooling fan if pushing many amps

www.aliexpress.com

3.95US $ 15% OFF|Dc-dc 5-30v To 1.25-30v 12v 24v 8a Automatic Adjustable Step Up Down Boost Buck Converter Power Module Voltage Regulator For Car - Voltage Regulators/stabilizers - AliExpress

Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com www.aliexpress.com
Click to expand...

I do have a couple converters that look exactly like that one (mine came from China seller on eBay), and they do work, as long as they mention they are buck/boost. Mine that look like that are buck/boost, but there may be look-alike-s out there that don't.

I've seen a dozen brands of these that essentially look identical, so just have to make sure. Those seem to be advertised as both buck/boost... Just saying, because there are counterfeits on a lot of the Chinese stuff as the manufacturers go out of their way to copy popular winning products...

Not to mention, there's no sense of speed when it comes to AliExpress orders, unless they offer a 'ships from USA' option, it can take 2 or more months to get one here (I've ordered plenty of stuff off AliExpress and it's fine if you're not in a hurry)..
 
Last edited:
Samsonite801 said:
I do have a couple that look just like that one (mine came from China seller on eBay), and they do work, as long as they mention they are buck/boost. Mine that look like that are buck/boost, but there may be look-alike-s out there that don't.

I've seen a dozen brands of these that essentially look identical, so just have to make sure. Those seem to be advertised as both buck/boost... Just saying, because there are counterfeits on a lot of the Chinese stuff as the manufacturers go out of their way to copy popular winning brands...

Not to mention, there's no sense of speed when it comes to AliExpress orders, unless they offer a 'ships from USA' option, it can take 2 months to get one here (I've ordered plenty off AliExpress and it's fine if you're not in a hurry)..
Click to expand...
these are specifically buck boost and I use them for situations precisely like the Op wants , ie a stable 12v , ie my Android downstairs helm information system repeater , various Arduinos boards , a raspberry pi etc I think I have 6 or 7 on the boat at the moment

yes Ali takes about 6-8 weeks, its like wine ,you keep an order stream flowing all year round !!!
 
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